Detection of proteins from circulating neoplastic cells

Abstract

The protein EGFR, ERCC1, RRM1, thymidylate synthase, or beta-tubulin from cancer cells is detected in a blood sample by enriching the cancer cells from the blood sample followed by performing on the enriched cancer cells an immunoassay capable of detecting the proteins mentioned above. Cancer patients overexpressing EGFR are treated with an anti-EGFR agent, for example cetuximab, panitumumab, erlotinib or gefitinib.

Description

BACKGROUND OF THE INVENTION[0001]This invention addresses a significant and unmet medical need of providing for sensitive immunoassays which allow for advancement in the field of personalized cancer therapy. The general concept of personalized medicine for cancer has been the subject of recent reviews (Zoon K C, 2004, Toxicology Pathol. 32(Suppl 1):1-2; MacGregor J T, 2004, Toxicology Pathol. 32(Suppl 1):99-105; Carr K M et al., 2004 Hum Genomics 1:134-40). The approach of personalized medicine for cancer is to characterize the proteins or genes in the patient's tumor in order to determine the best course of therapy. For example, expression of certain genes or gene patterns at either the protein or mRNA level may predict either sensitivity or resistance to various classes of anticancer agents. Based on the expression in the patient's tumor, an agent may be selected for therapy or rejected for use in that particular patient. Table 1 lists some of the proteins whose overexpression is ...

AI Technical Summary

Benefits of technology

[0008]The detection and assay methods described are convenient, quick and objective. Convenience: The approach outlined in this invention does not rely on the need for biopsy material. The patient's blood sample can be directly analyzed for the expression of the certain proteins in circulating tumor cells. Quick: Compared to IHC, the immunoassay of this invention avoids the need to retrieve blocks of tissue, de-paraffinize the blocks, cut slides and perform and interpret staining. Instead, a rapid immunoassay is used. Objective: Using the immunoassay of this invention, subjective scoring such as with IHC is avoided.

Problems solved by technology

A major impediment for the advance in this field is the lack of a convenient, quick and objective assay to determine overexpression of such proteins.

(2005, J Clin Oncol 22:5148-54), such an approach is time-consuming and often can give misleading results depending upon how the tissue was processed.

Henson, D. E. (2005, J Natl Cancer Inst 97:1796-7) in his paper entitled: “Back to the Drawing Board on Immunhistochemistry and Predictive Markers”, indicates that with so many variables (storage of the specimen, duration of fixation, type of fixative and conditions of tissue processing) and problems associated with each of them, it is difficult to properly control IHC testing and for all laboratories to “accept and sustain [these controls] seem impossible to realize.”

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